Blackspot and rose breeding article



I was hoping they were going to compare species.

Vance, Kathy, and Stan are good friends. It was my pleasure to help with this research by providing my Honeybee rose and helping to innoculate plants and brainstorm ideas along the way. I think Vance did a great job characterizing North American races and challenging common ideas of horizontal versus vertical resistance as he shows some flip flopping in amount of disease based on isolate in some roses which doesn’t fit with the over simplistic way horizontal versus vertical resistance is often portrayed in the text books. He has a paper accepted and soon to be published on the molecular characterization of diversity of blackspot isolates describing the role of geography and hosts on pathogen populations.

Vance’s emphasis now for his Ph.D. is more on the host than the pathogen. He has breeding populations segregating for resistance to characterize inheritance of resistance and characterize different parents for their combining ability for resistance. Last summer he went to work in Dr. Thomas Debener’s lab in Germany to work on resistance gene analogs in rose. I look forward to what he learns about blackspot resistance mechanisms, genes, and inheritance of resistance as he continues his work.




More studies like this one are needed.

This said if scientific minded we have to make critics.

Isn’t this a curious idea to challenge common ideas of horizontal versus vertical resistance when tests are made on a few selected for ornamental character clones.

Are not the tests portrayed in the text books concerning large populations that bred for many generations with pathogen presence.

Isn’t pathogen presence generally excluded for roses at first selection stage. And later usually repressed.

With Robert I regret the study was not at local species ample samples.

Another critic this “challenging” may be at least partially reduced to different environmental (temperature?) optimums for both pathogen strains virulence and plant resistance expression.

This different temperature linked pathogen-host relationship is annualy observed.

Actually here it is time for “rose innocence” with low pathogen pressure and the lower temps roses obviously prefer.